1) Field of the Invention
The present invention relates to a wiring board that forms a communication circuit by selecting a set of primary side ports and a set of secondary side ports from among many primary side and secondary side ports, and connecting the primary side ports and the secondary side ports via an optical connection cable.
2) Description of the Related Art
A patch panel board as an example of a wiring board according to a conventional technique is explained with reference to the accompanying drawings. FIG. 6 is an explanatory diagram of a connector of the patch panel board according to the conventional technique. Many connector units are actually present at the primary side and the secondary side, respectively. However, for the sake of simplicity of explanation, only connector units to be connected are shown at the primary side and the secondary side, respectively.
As shown in FIG. 6, the connector according to the conventional technique has a primary side light cord 1, a secondary side light cord 2, an optical connection cable 3, a primary side connector unit 4, and a secondary side connector unit 5.
A primary side optical connector 1a is formed at a terminal of the primary side light cord 1. This primary side optical connector 1a is accommodated in the primary side connector unit 4. A secondary side optical connector 2a is formed at a terminal of the secondary side light cord 2. This secondary side optical connector 2a is accommodated in the secondary side connector unit 5. A primary side optical connector 3a and a secondary side optical connector 3b are formed at both side terminals of the optical connection cable 3.
As shown in FIG. 6, when the primary side optical connector 3a of the optical connection cable 3 is accommodated in the primary side connector unit 4, the primary side optical connector 1a and the primary side optical connector 3a are disposed oppositely and are optically connected to each other.
When the secondary side optical connector 3b of the optical connection cable 3 is accommodated in the secondary side connector unit 5, the secondary side optical connector 2a and the secondary side optical connector 3b are disposed oppositely and are optically connected to each other.
By this arrangement, the primary side light cord 1 and the secondary side light cord 2 are connected together via the optical connection cable 3.
According to this connection of the patch panel board, an operator first searches a primary side connector unit and a secondary side connector unit of corresponding ports with reference to a work instruction manual (a port connection table), and inserts a primary side optical connector and a secondary side optical connector of an optical connection cable. Then, the operator checks whether the connection is correct, using actual optical data or the like. After the confirmation, the operator enters a port management table of the primary side port and the secondary side port connected, respectively. At each port of the primary side and the secondary side, address information is displayed using a card (write system), or display of address information is omitted.
According to this conventional technique, there are (1) a possibility of a connection error, and (2) a possibility of a description error (such as a writing error, and an erroneous omission of description) by the operator, which are management errors.
In order to decrease such management errors, various measures are taken. A conventional technique to decrease these errors is explained with reference to the drawings. FIG. 7 is an explanatory diagram of a connector of a patch panel board according to another conventional technique. This patch panel board has a primary side inductive LED (light-emitting diode) 6a, a secondary side inductive LED 6b, a display driver 7, a connection setting data storage 8, and a setting display section 9, in addition to the parts in the conventional technique shown in FIG. 6.
According to this patch panel board, connection setting data to indicate a primary side connector and a secondary side connector to be connected can be input. When the operator operates the setting display section (specifically, a personal computer) 9 to input connection setting data, a display section (specifically a display of the personal computer) of the setting display section 9 displays the connection setting data. This connection setting data is provisionally stored in the connection setting data storage 8, and is output to the display driver 7. When the display driver 7 outputs a primary side LED control signal and a secondary side LED control signal as electric signals necessary for light emission to the set primary side inductive LED 6a and the set secondary side inductive LED 6b, respectively, one primary side inductive LED 6a and one secondary side inductive LED 6b that are selected from among many LEDs are lit up. The primary side connector unit 4 to be connected is selected by the light-emitting primary side inductive LED 6a, and the secondary side connector unit 5 to be connected is selected by the light-emitting secondary side inductive LED 6b. 
According to this conventional technique, there is an advantage that a port to be connected can be selected easily, and the number of connection errors can be decreased.
The conventional techniques are explained above with reference to FIG. 6 and FIG. 7. There is another conventional technique of a patch panel board as described in a Patent Literature 1 (Japanese Patent Application Laid-Open No. 2001-145221 (Paragraph No. 0012 to 0030, FIGS. 1 to 4), Title of the invention: Terminal Identification Cable). According to this conventional technique, an optical fiber is disposed around an external periphery of a cable that connects a device, along a total length of the cable. Light is irradiated at one end of the optical fiber to emit light from the other end of this optical fiber, thereby identifying the cable in an improved manner. This method prevents wiring errors and can improve work efficiency.
There is still another conventional technique of a patch panel board as described in a Patent Literature 2 (Japanese Patent Application Laid-Open No. H6-260235 (Paragraph No. 0017 and 0018, FIG. 2), Title of the invention: Wiring Connecting Device and Wiring Connecting Method). This conventional technique applies to a metal cable instead of a light cord. A connection position is informed using an LED like the conventional technique as explained with reference to FIG. 7.
In order to avoid the above errors in managing the patch panel board, there is a demand for a patch panel board that has (1) a connection error preventing function of accurately connecting between targeted ports, and (2) a connection error managing function of accurately managing the connected ports.
However, the patch panel board according to the conventional technique as shown in FIG. 7 does not have the above functions. According to the patch panel board shown in FIG. 7, the primary side inductive LED and the secondary side inductive LED are fitted to the primary side connector unit and the secondary side connector unit, respectively. The connection error preventing function (1) is achieved by informing by emitting light from the port to be connected. However, after the connection, the conventional management method is applied. (In other words, after the light cord is inserted, the operator confirms whether the ports are actually connected, and enters the management table.) Thus, this patch panel board does not achieve both the connection error preventing function and the connection error monitoring function. The patch panel board according to the conventional technique described in the Patent Literature 1 does not achieve the both functions either.
According to the conventional technique described in the Patent Literature 2, a connection is confirmed based on induction using an LED display, or by using one line as a connection confirmation line out of six lines. However, this method cannot be easily applied to a patch panel board using a light cord. When an optical connection cable in which light cords of communication lines and a connection confirmation line is used for the connection confirmation, a light cord for connection confirmation, an E/O (electrical to optical) converter, and an O/E (optical to electrical) converter are necessary corresponding to the number of ports, which results in a substantial increase in cost. In the case of the optical connection cable in which plural light cords run, connectors must face each other at accurate positions in the primary side connector unit and the secondary side connector unit. However, connector positions are deviated due to force of the optical connection cable which cannot be easily bent because of the plural light cords. This makes it difficult to successfully carry out optical signal communications, which may possibly lead to a connection error. Since the connectors are correctly connected in the primary side connector unit and the secondary side connector unit, this connector error cannot be easily determined, which may make it difficult to carry out management.